Printing die and retaining means therefor



March 9, 1937. l. J. KLEIN 2,073,308

PRINTING DIE AND RETAINING MEANS THEREFOR Filed Nov. 1, 1935 Patented Mar. 9, 1937 UNITED STATES PATENT OFFICE PRINTING DIE AND RETAINING MEAN S THEREFOR 9 Claims.

This invention relates to improvements in retaining devices for signature dies for multigraphs and the like.

An object of the invention resides in the novel base plate for the signature die.

A further object of the invention is found in the adjustable clamps for retaining the die and its base plate on the drum of a signature attachment or device for multigraphs.

With the above and other objects in view, my invention consists in the novel combination and construction of the various parts and members shown in preferred form in the attached drawing, described in the following specification and particularly pointed out in the appended claims.

Referring to the drawing:

Fig. 1 is a view, in perspective, showing my new and improved die and its supporting base and retaining clamps; one of the clamping members and its retaining screw being shown in detached position.

Fig. 2 is an enlarged cross section. V

Fig. 3 is an enlarged cross section through'the" signature die.

Referring to thedie which is generally indicated by ill, the die material consists preferably of two layers A and B of rubber separated by a rubberized canvas or fabric C. v

The letters or portions of the signature are formed with sloping or diagonal walls, indicated by E. The lower rubber portion B is cemented to cause same to adhere to a supporting base plate II.

The base plate II is formed to securely retain the die I and is preferably of metallic material and arcuate in cross section. The curved crosssectional form is preferably made with a radius which is greater than the radius of the drum I2 to which it is attachable so that it may be forcibly pressed into perfect fit against the drum l2 and thus prevent any high or low spots which cause distortion in parts of the printing.

The base plate I l is also formed, on the edges of its two opposite sides, with a plurality of spaced integral prongs II which are bent up to retain between them and the curved body portion, the die I0. Obviously these prongs II may be fabricated in any suitable form or spacing and their number may also be varied, or the opposed edges of the base plate II might readily be bent over in the form of a single flange.

The rubber die I0, and its supporting base plate II is securely attachable to the curved surface of a cylindrical drum I2 by means of a pair of elongated arcuate retaining plate clamps I3 extending lengthwise on and along the sides of the plate I I.

The cross sectional arcuate form of the clamps I3 is preferably made with a radius which is shorter than the radius of the drum l2 and the two side edges of the clamps I3 are beveled or out obliquely as at IS to afford a larger surface contact of the sides of the clamp plates l3 against the drum I2 and the base plate I l than would be possible with the corners of square edges of the clamps I3.

The clamps l3 are also made preferably of a resilient metal so that when they are securely tightened to the drum l2 by means of the screws I 4 they will be slightly flexed upon the tightening of the screws Hi to thereby impose sufl'icient' pressure along their beveled edges to securely frictionally flex and retain the die plate II onto the drum l2.

It will also be noted, that the holes I 3 in the clamps I3 are elongated in a direction to afford crosswise adjustment of the clamps I3 relatively to the die supporting plate II.

It will'also be observed that since the die and its supporting platel I is only frictionally heldby l I may be readily' the clamps l3, such die plate shifted to provide adjustment thereof longitudinally of the drum I2 by simply loosening the clamp-securing screws I 4.

I claim:

1. Printing means for multigraphs and the like, including a printing die of flexible material, a flexible metallic base plate to which said printing die is secured, said base plate having a normal arcuate cross-sectional form and being adapted to be mounted on and to extend longitudinally of a rotary member of the multigraph, the arcuate form of said base plate being formed with a greater radius than the radius of said rotary member, and tightening means for retaining said base plate on said rotary member, said tightening means being adapted upon tightening to exert pressure on said base plate to cause a deflection of the normal arcuate form of said base plate to conform same to the curvature of the surface of said rotary member.

2. Printing means as embodied in claim 1, and including said tightening means comprising a pair of flexible transversely arcuate elongated metallic plates, one side of each of said tightening plates engaging one side of the base plate.

3. Printing means as embodied in claim 1, and including said tightening means comprising a pair of flexible transversely arcuate elongated metallic plates, one side of each of said tightening plates engaging one side of the base plate, said tightening plates having an arcuate crosssection formed with a radius which is shorter than the radius of said rotary member.

4. In a printing mechanism having a cylindrical rotary roller, a printing die mounted on a flexible metallic base plate, said base plate extending longitudinally of and over a portion of said cylindrical roller and having a normally arcuate cross-section the radius of which is greater than the radius of said cylindrical roller, clamping means mounted on said cylindrical roller to retain said base plate, said clamping means engaging the sides of said base plate, and means for exerting pressure on said clamping means for retaining said clamping means on said cylindrical roller and for retaining said base plate flexed to conform to the curvature of the surface of said cylindrical roller.

5. In a printing mechanism having a cylindrical roller and printing die mounted on a flexible metallic base plate, said base plate extendlongitudinally of and over a portion of said cylindrical roller and having a normally arcuate crosssection the radius of which is greater than the radiusof said cylindrical roller, clamping means mounted on said cylindrical roller to retain said base plate, said clamping means comprising a pair of plates having a normally arcuate crosssection the radius of which is shorter than the radius of said cylindrical roller and being arranged for engaging the sides of said base plate, and means for exerting pressure on said clamping means for retaining said clamping means on said cylindrical roller and for retaining said base plate flexed to conform to the curvature of the surface of said cylindrical roller.

6. A support for a printing die of flexible material, said support being adapted to be secured to a curved surface of a cylindrical drum and to extend longitudinally of said drum and comprising a plate of flexible material of a normally arcuate cross-section the radius of which is longer than the radius of said drum, means for retaining the printing die on said plate, and means for retaining said plate on said drum,

said plate being adapted to be flexed in crosssection by pressure of said retaining means to conform to the curvature of the surface of said drum.

'1. In clamping means for a printing device having a cylindrical drum and a printing die supported on an elongated flexible metallic plate member of normally arcuate cross-section of a different curvature than the curvature of the surface of said drum, said clamping means comprising a pair of elongated flexible plates of arcuate cross-section, each of said elongated flexible clamping plates having one side in engagement with a side of said die-supporting plate member, and pressure-exerting means for removably securing said clamping plates to said drum and to said die-supporting plate member to thereby flex said die-supporting plate member to conform it to the curvature of the surface of said cylindrical drum.

,8. In clamping means as embodied in claim 7, and including each of said clamping plates having the two longitudinal side edges thereof formed obliquely to the faces of the plates.

9. A unitary printing die adapted to be secured to a cylindrical drum, said printing die including an elongated flexible metallic base plate of normally arcuate cross-section of a different curvature than the curvature of the surface of said cylindrical drum, a printing structure secured to the convex face of said plate and comprising an outer layer of resilient material having printing characters formed on the outer face thereof, a cushion of resilient material mounted adjacent the convex face of said plate, a layer of thin fabric mounted between said outer layer of resilient material and said cushion material, and pressure-exerting means for flexing said plate and said printing structure to conform the curvature of said plate and said printing structure to the curvature of the surface of the cylindrical drum, said pressure-exerting means being adapted to secure the unitary printing die to the drum.

IRVING J. KLEIN. 

